#include <iostream>
#include <algorithm>

using namespace std;

const int &MAX = 200000;

int main() {
    int R[MAX], n;
    cin >> n;
    for (int i = 0; i < n; ++i) cin >> R[i];

    int maxv = -2000000000;
    int minv = R[0];

    for (int i = 1; i < n; ++i) {
        maxv = max(maxv, R[i] - minv);
        minv = min(minv, R[i]);
    }

    cout << maxv << endl;
    return 0;
}